com.kheops.jmap.readers

Class SpatialFileReader

java.lang.Object

com.kheops.jmap.readers.SpatialFileReader

Direct Known Subclasses:

APICReader, DGN7Reader, DGNReader, DWGReader, GeoJsonReader, GMLReader, GMLReaderV2, IFCReader, KMIFReader, KShapeReader, KTXTReader, NMEAReader, OgrReader, PhotoReader

public abstract class SpatialFileReader
extends java.lang.Object

This abstract class must be extended by file readers of geographical data formats in order to use them as data sources in JMapServer. This mechanism is part of the abstraction layer between the various existing formats and JMap.

By extended this class, subclasses can provide geometrical data as well as attribute data on a row by row basis.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	geometryTypesFilter The geometry types filter.
static java.lang.String	READER_PARAM_FILES
static java.lang.String	READER_PARAM_LAYERS

Constructor Summary

Constructors

Constructor and Description
SpatialFileReader()

Method Summary

Modifier and Type	Method and Description
abstract void	close() Frees the resources used by the reader implementation.
abstract Attribute[]	getAttributeMetaData() Gets the metadata associated with the data source.
abstract int	getAvailableGeometryTypes()
int	getGeometryTypesFilter() Returns the geometry types filter which is currently used.
abstract java.lang.String[]	getLayers() Returns an array of String that defines the layers found in the SpatiaDataSource
abstract java.lang.String	getName()
abstract JMapGeoElement	getNext() Gets the next element from the data source.
protected static java.lang.String	getNextColunmName(Attribute[] attributeMetaData) Returns the next available name for the attributeMetaData.
abstract java.lang.String	getParametersParserClassName()
abstract java.lang.String[]	getPaths(java.lang.String params) Returns an array of String which defined the file paths used by the reader.
abstract long	getTimeStamp() Gets time stamp of the data file.
abstract java.lang.String	getVersion()
abstract boolean	hasNext() Determines if there are any more information to read using the getNext method.
protected static boolean	isColunmNameExists(java.lang.String name, Attribute[] attributeMetaData) Returns whether Attribute already contains the specified name.
static SpatialFileReader	loadReader(java.lang.String className)
abstract void	open(java.lang.String params) This method opens the file for the specified layer and sets the its parameters.
abstract void	reset() Resets the state of the reader so that the next call to getNext will return the first element of the data source.
void	setGeometryTypesFilter(int geometryTypesFilter) Sets the geometry types filter to use while reading a spatial file.
protected void	validateMetaData(Attribute[] attribs1, Attribute[] attribs2) This method can be used to verify the equality between two Attribute arrays.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

READER_PARAM_FILES

public static final java.lang.String READER_PARAM_FILES

See Also:

Constant Field Values

READER_PARAM_LAYERS

public static final java.lang.String READER_PARAM_LAYERS

See Also:

Constant Field Values

geometryTypesFilter

protected int geometryTypesFilter

The geometry types filter. Geometries can be added or removed using bit operations like OR, AND, XOR and NOT.

Constructor Detail

SpatialFileReader

public SpatialFileReader()

Method Detail

getName

public abstract java.lang.String getName()

getVersion

public abstract java.lang.String getVersion()

getParametersParserClassName

public abstract java.lang.String getParametersParserClassName()

open

public abstract void open(java.lang.String params)
                   throws java.lang.Exception

This method opens the file for the specified layer and sets the its parameters.

Parameters:

params - the string containing the parameters for the layer.

Throws:

java.lang.Exception

reset

public abstract void reset()
                    throws java.lang.Exception

Resets the state of the reader so that the next call to getNext will return the first element of the data source.

Throws:

java.lang.Exception

hasNext

public abstract boolean hasNext()
                         throws java.lang.Exception

Determines if there are any more information to read using the getNext method.

Returns:

true if there is at least one more element to read, false otherwise

Throws:

java.lang.Exception

See Also:

getNext(), reset()

getNext

public abstract JMapGeoElement getNext()
                                throws java.lang.Exception

Gets the next element from the data source. Availability should be checked first using method hasNext.

Returns:

the next JMapGeoElement object

Throws:

java.lang.Exception

See Also:

hasNext(), reset(), JMapGeoElement

getAttributeMetaData

public abstract Attribute[] getAttributeMetaData()
                                          throws java.lang.Exception

Gets the metadata associated with the data source. The metadata provides information about the descriptive data columns bound to the geometrical data of the data source. N.B: This method has to take care of possible duplicate attribute name.

Returns:

an array of Attribute instance.

Throws:

java.lang.Exception

See Also:

Attribute

getTimeStamp

public abstract long getTimeStamp()
                           throws java.lang.Exception

Gets time stamp of the data file. This time stamp can be used to determine if the data has changed since it was last accessed.

Returns:

the time stamp (number of milliseconds since Jan. 1st 1970) of the data file or -1 if not supported by the implementation of the reader

Throws:

java.lang.Exception

close

public abstract void close()
                    throws java.lang.Exception

Frees the resources used by the reader implementation. Some implementations require that this method be called after use while other implementations don't.

Throws:

java.lang.Exception

getPaths

public abstract java.lang.String[] getPaths(java.lang.String params)

Returns an array of String which defined the file paths used by the reader.

Parameters:

params - the parameters used to open the SpatialFileDatasource

Returns:

the file paths used by the reader.

getLayers

public abstract java.lang.String[] getLayers()
                                      throws java.lang.Exception

Returns an array of String that defines the layers found in the SpatiaDataSource

Returns:

an array of String or null if the SpatiaDataSource doesn't support layers

Throws:

java.lang.Exception

getAvailableGeometryTypes

public abstract int getAvailableGeometryTypes()
                                       throws java.lang.Exception

Throws:

java.lang.Exception

getGeometryTypesFilter

public int getGeometryTypesFilter()

Returns the geometry types filter which is currently used.

Returns:

Returns the geometryTypesFilter.

setGeometryTypesFilter

public void setGeometryTypesFilter(int geometryTypesFilter)

Sets the geometry types filter to use while reading a spatial file.

Parameters:

geometryTypesFilter - The geometryTypesFilter to set.

validateMetaData

protected void validateMetaData(Attribute[] attribs1,
                                Attribute[] attribs2)
                         throws java.lang.IllegalArgumentException

This method can be used to verify the equality between two Attribute arrays.

Parameters:

attribs1 - an array of Attribute objects.

attribs2 - the array of Attribute objects that will be verified.

Throws:

java.lang.IllegalArgumentException - if the two specified arrays don't contain exactly the same attributes.

loadReader

public static SpatialFileReader loadReader(java.lang.String className)

isColunmNameExists

protected static boolean isColunmNameExists(java.lang.String name,
                                            Attribute[] attributeMetaData)

Returns whether Attribute already contains the specified name. First name is K2DText.ATTRIBUTE_TEXT_VALUE.

Parameters:

Attribute - the Array of Attributes to use.

name - the name to search.

Returns:

false if the specified name was not found.

getNextColunmName

protected static java.lang.String getNextColunmName(Attribute[] attributeMetaData)

Returns the next available name for the attributeMetaData.

Parameters:

Attribute - the Array of Attributes to search.

Returns:

the next available name for the attributeMetaData.